Electrophotographic belt, electrophotographic image forming apparatus and cured rubber product

Abstract

An electrophotographic belt comprising: a substrate and an elastic layer on an outer peripheral surface of the substrate, the elastic layer comprising a cured rubber product including a cured silicone rubber product, an elastic modulus of the elastic layer at a temperature of 23° C. being 1.00 MPa or less, wherein when 1 g sample collected from the elastic layer is immersed in 50 ml of toluene at a temperature of 23° C. for 24 hours in accordance with Japanese Industrial Standard (JIS) K6258:2016, an extract of 3% by mass to 20% by mass with respect to the sample is extracted, and a burning time of the elastic layer in a burn test in accordance with UL94 VTM standard is 30 seconds or less.

What is claimed is: 
     
         1 . An electrophotographic belt comprising:
 a substrate and an elastic layer on an outer peripheral surface of the substrate,   the elastic layer comprising a cured rubber product including a cured silicone rubber product,   an elastic modulus of the elastic layer at a temperature of 23° C. being 1.00 MPa or less,   wherein   when 1 g sample collected from the elastic layer is immersed in 50 ml of toluene at a temperature of 23° C. for 24 hours in accordance with Japanese Industrial Standard (JIS) K6258:2016, an extract of 3% by mass to 20% by mass with respect to the sample is extracted, and   a burning time of the elastic layer in a burn test in accordance with UL94 VTM standard is 30 seconds or less.   
     
     
         2 . The electrophotographic belt according to  claim 1 , wherein the extract comprises at least two organopolysiloxanes selected from the group consisting of:
 an organopolysiloxane having a first structure represented by a following formula (1),   an organopolysiloxane having a second structure represented by a following formula (2), and   an organopolysiloxane having a first structure represented by the following formula (1) and a second structure represented by the following formula (2):   
       
         
           
           
               
               
           
         
         where in formulas (1) and (2), R 11 , R 12 , and R 13  each independently represent an unsubstituted or substituted monovalent hydrocarbon group that does not contain an unsaturated aliphatic group. 
       
     
     
         3 . The electrophotographic belt according to  claim 2 , wherein B/(A+B) is from 0.1 to 0.5, where A is a number of moles of the first structure in the extract, and B is a number of moles of the second structure in the extract. 
     
     
         4 . The electrophotographic belt according to  claim 3 , wherein B/(A+B) is from 0.1 to 0.3. 
     
     
         5 . The electrophotographic belt according to  claim 2 , wherein the unsaturated aliphatic group is a vinyl group. 
     
     
         6 . The electrophotographic belt according to  claim 1 , wherein the elastic modulus of the elastic layer is 0.18 MPa or more. 
     
     
         7 . The electrophotographic belt according to  claim 1 , wherein the cured rubber product is a cured product of an addition-curable liquid silicone rubber including (a) an organopolysiloxane having an unsaturated aliphatic group, (b) an organopolysiloxane having a hydrosilyl group, and (c) a hydrosilylation catalyst. 
     
     
         8 . The electrophotographic belt according to  claim 7 , wherein a molar ratio (H/Vi) in the addition-curable liquid silicone rubber is from 0.5 to 1.5, the molar ratio (H/Vi) being a molar ratio of a moiety Si—H of which a hydrogen atom is directly bonded to a silicon atom to the unsaturated aliphatic group. 
     
     
         9 . The electrophotographic belt according to  claim 1 , wherein the elastic layer has a thickness of from 50 μm to 500 μm. 
     
     
         10 . The electrophotographic belt according to  claim 1 , wherein the electrophotographic belt is an intermediate transfer belt. 
     
     
         11 . An electrophotographic image forming apparatus comprising an electrophotographic belt, wherein the electrophotographic belt comprises a substrate and an elastic layer on an outer peripheral surface of the substrate,
 the elastic layer comprises a cured rubber product including a cured silicone rubber product,   an elastic modulus of the elastic layer at a temperature of 23° C. is 1.00 MPa or less,   when a 1 g sample collected from the elastic layer is immersed in 50 ml of toluene at a temperature of 23° C. for 24 hours in accordance with Japanese Industrial Standard (JIS) K6258:2016, an extract of 3 to 20% by mass with respect to the sample is extracted, and   a burning time of the elastic layer in a burn test in accordance with UL94 VTM standard is 30 seconds or less.   
     
     
         12 . A cured rubber product comprising a cured silicone rubber product,
 the cured rubber product having an elastic modulus at a temperature of 23° C. of 1.00 MPa or less, wherein   when 1 g sample collected from the cured rubber product is immersed in 50 ml of toluene at a temperature of 23° C. for 24 hours in accordance with Japanese Industrial Standard (JIS) K6258:2016, an extract of from 3 to 20% by mass with respect to the sample is extracted, and wherein   the cured rubber product has a burning time in accordance with UL94 VTM standard of 30 seconds or less.   
     
     
         13 . The cured rubber product according to  claim 12 , wherein the extract comprises at least two organopolysiloxanes selected from the group consisting of:
 an organopolysiloxane having a first structure represented by a following formula (1),   an organopolysiloxane having a second structure represented by a following formula (2), and   an organopolysiloxane having a first structure represented by the following formula (1) and a second structure represented by the following formula (2):   
       
         
           
           
               
               
           
         
         where in formulas (1) and (2), R 11 , R 12 , and R 13  each independently represent an unsubstituted or substituted monovalent hydrocarbon group that does not contain an unsaturated aliphatic group. 
       
     
     
         14 . The cured rubber product according to  claim 13 , wherein B/(A+B) is from 0.1 to 0.5, where A is a number of moles of the first structure in the extract, and B is a number of moles of the second structure in the extract 
     
     
         15 . The cured rubber product according to  claim 14 , wherein B/(A+B) is from 0.1 to 0.3. 
     
     
         16 . The cured rubber product according to  claim 12 , wherein the elastic modulus of the cured rubber product is 0.18 MPa or more. 
     
     
         17 . The cured rubber product according to  claim 12 , wherein the cured rubber product is a cured product of an addition-curable liquid silicone rubber including (a) an organopolysiloxane having an unsaturated aliphatic group, (b) an organopolysiloxane having a hydrosilyl group, and (c) a hydrosilylation catalyst.